Igniting system



March 9, 1965 c. o. GLASGOW ETAL 3,

'IGNITING SYSTEM Filed June 30, 1961 5 Sheets-Sheet 1 s a g -FUEL SUPPLY a rr INVENTORS CLARENCE O. GLASGOW WILLIAM E. COPPLE ATTORNEY March 1965 c. o. GLASGOW ETAL 7 3,172,456

IGNITING SYSTEM Filed June 30, 1961 5 Sheets-Sheet 2 3 mm 3% m m g m k O In 1 N a m H X l s m J E 0 BY M xdw ATTORNEY March 1965 c. o. GLASGOW ETAL 3,172,456

IGNITING SYSTEM 5 Sheets-Sheet 3 Filed June 30. 1961 xqllbm 45 1 -Q F MM twmsalu msS Q INVENTORS CLARENCE 0. GLASGOW WILLIAM E. COPPLE BY 65% Kala/4 ATTORNEY March 9, 1965 c. o. GLASGOW ETAL 7 IGNITING SYSTEM Filed June 30. 1961 5 Sheets-Sheet 5 FUEL SUPPLY SUPPLY INVENTORS CLARENCE O. GLASGOW WILLIAM E. COPPLE BY an gzjb ATTORNEY i I I I II |l United States Patent 3,172,456 IGNITING SYSTEM Clarence 0. Glasgow and William E. Copple, Tulsa, Okla, assignors to National Tank Company, Tulsa, mike, a corporation of Nevada Filed June 30, 1961, Ser. No. 122,387 15 Claims. (Cl. 158--125) The present invention relates to igniting burners. More particularly, the invention relates to a system for automatically igniting burners safely and on a predetermined program.

The control systems for burners in oil field processing units should be simple and reliable under rugged conditions in oil fields. At the same time, specific functions are desirable for these systems to obtain safety and efficiency.

To begin with, the day of personnel making personal visits to equipment and igniting burners with hand torches is over. Pilot burners are now required to ignite the main burners of processing equipment. Further, both some form of automatic ignition of the pilot burner and automatic ignition of the main burner from the pilot burner is required.

When there is no requirement for heat, and the main burner is consequently shut down, the pilot burner flame may be blown out by stray winds. A problem exists in automatically igniting the extinguished pilot burner, automatically proving the pilot burner to be operative and then automatically igniting the main burner from the pilot burner as the demand for heat again develops.

When the pilot burner is blown out accidentally, it is often required that a period of delay be provided before the automatic system be energized to ignite the pilot burner. This time delay enables the firetubc, or other burner housings, to be purged of an explosive mixture of fuel and air which may have been developed in the firetube-housing by the extinguished burner.

Another problem is found in providing for the automatic igniting equipment of the system to go through the cycle of operation a limited number of times. Should ignition attempts fail after a certain length of time, or number of cycles, it is desirable for the ignition system to shut down and signal for special attention from operating personnel.

Also, it is a problem to provide a means for developing an igniting electrical spark for the burner with apparatus simple and rugged enough to stand up under the demands of field service. A battery has a limited life under the best of conditions. Conventional, motor-driven generators are complex and their moving parts are vulnerable to the wear and tear and the dirty conditions of oil fields. Line supplies are often not available at the remote locations of oil field operations. The present invention is embodied in a system which utilizes a device which generates the required electrical spark without problems which have plagued this art for so many years.

The principal object of the present invention is to ignite a burner of fluid fuel automatically when the fluid fuel is made available at the burner by transducing the pressure of the fluid fuel into an igniting spark at the burner.

Another object is to limit the time the igniting spark is supplied the burner.

Another object is to provide a time lapse after the burner has been accidentally blown out before the igniting spark and fuel are supplied the burner for relighting.

Another object is to provide a continuous flow of fuel to an automatically ignited burner when the temperature of the combustion at the ignited burner reaches a predetermined level.

Another object is to first ignite a first burner of fluid 3,172,456 Patented Mar. 9, 1965 fuel automatically when the fluid fuel is made available and then automatically ignite a second burner with the flame of the first burner when the temperature of the combustion at the first burner reaches a predetermined level.

Another object is to carry out the ignition with only the energy of the pressure of the fluid fuel.

The present invention contemplates a fluid pressure motor responsive to the pressure of fluid fuel as the fluid fuel is supplied a burner, the motor arranged to apply mechanical pressure to piezoelectric material to develop an igniting spark at the burner.

The invention further contemplates the fluid fuel to which pressure of the motor responds, flowing from a limited volume of the fluid fuel. volume of fluid fuel without combustion temperature being reached at the burner then establishes the time the igniting spark is available for lighting the burner.

The invention further contemplates an arrangement in which a volume chamber is connected to the source of fluid fuel when the pilot burner is accidentally blown out. The volume chamber then fills with fuel to a predetermined pressure. The pressure then starts the automatic ignition of the burner and supply of fuel to the burner. The time for the chamber to reach the predetermined pressure establishes a safety time lapse to enable any explosive mixture of fuel and air in the vicinity of the burner to dissipate.

The invention contemplates providing a temperature sensitive element at the pilot burner to indicate when combustion at the burner has been established. The temperature element develops a force at a predetermined combustion temperature which connects the source of fuel to the burner as long as the predetermined temperature level is maintained.

The invention contemplates a complete system of a first, or pilot, burner and a second, or main, burner. The first burner is positioned to light the main burner, and the temperature element of the first burner controls the connection of the supply of fuel to the main burner. The temperature element not only connects the first burner to the fuel source at a predetermined temperature, but also connects the main burner to the fuel source.

The invention contemplates that the ignition of the burners be initiated by a transduction of the pressure energy of the fluid fuel into an igniting spark of electrical energy. The pressure is applied to a piezoelectric material which produces a sufliciently large spark to ignite the fuel and air mixture from the burner.

Other objects, advantages and features of this invention will become apparent to one skilled in the art upon consideration of the written specification, appended claims, and attached drawings wherein;

FIG. 1 is an elevation of an igniting system embodying the invention, the units of the system sectioned to illustrate their function;

FIG. 2 is a somewhat diagrammatic elevation of essential structure of the pressure-electric transducer included in the system;

FIG. 3 is a somewhat diagrammatic illustration of a complete industrial pilot-main burner system utilizing the invention; and

FIGS. 4, 4A and 4B are all somewhat diagrammatic illustrations of an industrial pilot-main burner system embodying the invention, the units of the system in the various positions required for cyclic operation.

BASIC IGNlTING SYSTEM FIG. 1 illustrates a basic embodiment of the invention. In FIG. 1 an industrial burner 1 is supplied fluid fuel from a source through conduit 2. The pressure energy of the fluid fuel is utilized by taking a portion of the fuel into The depletion of the 3 connecting conduit 3 and applying this pressure to operate spark pump 4. Spark pump 4 transduces the pressure of the fluid fuel into an electrical spark across the gap of plug 5. The electrical spark ignites the mixture of fuel and air. Combustion will continue at the burner so so long as fuel and air are supplied the burner.

The heat of combustion at burner 1 raises the temperature of shield 6. This elongated tube lengthens as its temperature increases. The end of shield 6 is attached to valve 7, and when the temperature of shield 6 reaches a predetermined level its elongation shuts valve 7. Valve 7 is in conduit 3, so when it is shut by the combustion heat of burner 1, spark pump 4 is isolated from the pressure of the fluid fuel and ceases to operate for so long as combustion is propagated at burner 1.

Heat responsive valve 7 The source of fluid fuel for conduit 2 is not shown. The fuel is mixed with air in burner 1 in the conventional manner. Once the mixture issues from burner 1, into the tubular shield 6, an igniting spark is all that is required to initiate combustion.

The fluid fuel taken into conduit 3 may be controlled by various valve arrangements. FIG. 1 shows a simple, twochamber housing for valve 7, the chamber 8 communicating with chamber 9 through an opening in a separating partition.

A valve element 10 is loaded by spring 11 to open until stem 12 is pulled to overcome the spring force. Valve element 10 then seats on the partition, covers the opening and prevents flow of fuel from chamber 8 to chamber 9.

Valve stem 12 is attached to the forward end of shield 6. A simple extension rod 13 from the shield end carries a fixture for one end of Wire 14. Wire 14 includes a spring 15 and attaches to valve stem 12. Spring 15 is sized to overcome the force of spring 11 when wire 14 is pulled by elongating tube 16. However, when valve 10 seats on the valve partition, further elongation of tube 6 will not cause wire 14 to fail. Spring 15 provides the means for not allowing continued elongation of tube 6 to rupture wire 14.

Spark pump 4 The pressure of the fluid fuel in conduit 3 passes to spark pump 4 so long as the heat responsive valve is open. This fluid pressure is periodically, or cyclically, applied to a spring-loaded diaphragm operator 16 to reciprocate a stem 17 attached to the operator. The motion of the stem 17 is then applied as a pressure to mechanically stress material capable of developing piezoelectricity and produce the igniting high spark voltage.

In FIG. 1, the diaphragm operator 1t: has been sectioned to show spring 18 loading a diaphragm 19 from its top while a conduit 20 is alternately connected to the fluid pressure of conduit 3 and atmosphere exhaust. The connection of conduit 20 to conduit 3 and exhaust is made by actuating three-way valve 21 from one of its two positions to the other.

Valve 21 is a three-way, two-position, snap-acting valve similar to that disclosed in at least United States Patent 2,860,660. The actuating stem of this valve is arranged to extend into engagement with abutments mounted on stem 17 of operator 16. As the stem 17 reciprocates, the abutments actuate valve 21 from one position to the other. As valve 21 is actuated, conduit 20 is alternately connected to conduit 3 and exhaust. As the underside of diaphragm 19 is alternately pressured and exhausted stem 17 is reciprocated. This cycle of functions continues so long as the pressure of the fluid fuel is applied to conduit 3.

The end of stem 17 rests on the end of lever arm 22. The opposite end of lever arm 22 is attached to a lever 23 which extends into housing 24. Housing 24 contains the pressure-stressed body which delivers electrical ener- 4. gy to the gap of plug 5. The lever system including 22 and 23 is simply actuated in a cycle. The result is delivery of electrical energy to plug 5 by connection 25.

Piezoelectric material of spark pump 4 FIG. 2 illustrates the essential elements of the trans ducer element of the spark pump. The commercial form of this mechanism is marketed by the Cleveland Graphite Bronze Division of the Clevite Corporation of Cleveland, Ohio. Advertized in several trade journals, the commer cial form of the spark pump is discussed in some detail in a paper entitled A Piezoelectric Ignition System for Small Engines by Edwin Crankshaw and R. Arnold for presentation at the 1961 SAE Summer Meeting, St. Louis, Missouri.

FIG. 2 illustrates that cylinders 30 and 31 are simply aligned and stressed, by the force of fulcrumed lever 23, from one end. A spring structure 32 bears on the op posite end of the aligned cylinders. Between the spring 32 and lever 23, the cylinders receive a mechanical input force of about 1200 pounds from the lever system to develop 16,000-19,000 volts with an energy level of about 0.15 joule at 18,000 volts. This energy is delivered to the gap of plug 5 to produce a high spark voltage which will ignite the mixture of fuel and air from burner 1 and in tubular shield 6.

The cylinders 30, 31 are mechanically aligned as illustrated. A metallic separator 33 between them is direct 1y attached to electrical wire 25, making a parallel electrical connection of the cylinders to plug 5. The material of the cylinders is preferably a lead-zirconate-titanate ceramic which has great stiffness and strength, excellent dielectric properties and a high piezoelectric effect.

FIG. 3 MAIN-PILOT BURNER SYSTEM Heretofore, the basic features of the invention have been disclosed in various ways. A single burner for fluid fuel has been disclosed, ignited by an electrical spark which is generated by the pressure energy of the burner fuel itself. It has been shown that the electrical spark need not be generated from the pressure energy of the fuel.

One common denominator of the foregoing embodi ments of the invention is the influence of the heat of combustion at the ignited burner. The heat of combustion has been utilized to terminate the spark generation. With the burner proved, is. supporting combustion at a predetermined level, the spark pump. is directly turned oft" until needed again.

FIG. 3 now discloses a more complete combustion system in which a larger, main burner is lit by a smaller, pilot, burner which was originally ignited in accordance with the invention as disclosed in the preceding drawings.

Further, the function of imposing a time delay in the system operation, for specific purposes, is implemented by structure disclosed in FIG. 3.

Pilot burner and spark pump supply In PEG. 3 a conduit so brings the fluid fuel to the" system from a source which is not shown. Conduit 61 removes a portion of the fluid fuel from conduit 60 to form a supply for connecting valve 62. From connecting valve 62, the fuel is routed through one of two paths to pilot burner 63.

The paths for fluid fuel to burner 63 from conduit 61 requires some detailed description. The first path is partially formed by conduit 64. This conduit 64 is seen to continue through check valve 55 until it joins with conduit 66. The first path then comprises both conduits. 64 and 66 with check valve 65 bewteen the conduits. As illustrated in FIG. 3, the fuel supplied the system flows, initially along this first path, from conduit ditto burner 63.,

The spark pump =67 in FIG. 3 is similar to the spark pump of FIGS. 1 and 2. The pressure energy of the fuel gas in the first path is supplied to operate spark pump- 67. To apply this fluid pressure, conduit. 68 is connected;

to conduit 64 ahead of check valve 65 so both the burner 63 and spark pump 67 are supplied simultaneously from the source of fluid fuel. After connecting valve 62 disconnects the first path, from the fuel source of conduit 61, the spark pump 67 ceases to operate.

Connecting valve 62 is a two-position, three-way snapacting valve similar to that used as a component of the spark pump. To operate valve 62, diaphragm operator 69 is driven to one of two positions by a spring and the spring force is then overcome by fluid pressure applied to the diaphragm in opposition to the spring to drive the operator in the other of its two positions. With connecting valve 62 actuated to its two positions, it can be discerned that FIG. 3 illustrates one of these two positions. Conduit 61 is disconnected from conduit 64 of the first path and connected to conduit 70 as a part of the second path for the fuel to burner 63. Specifically, conduit 70 connects to conduit 66 downstream of check valve 65. The complete second path then comprises conduit 70 and conduit 66, from connecting valve 62 to burner 63.

Time delay When fuel is supplied the system, spark pump 67 operates, generating an ignition spark at burner 63 to light the combustible mixture of fuel and air issuing from burner 63. The ignition spark is generated until the burner is proved and a predetermined interval of time has lapsed. The predetermined interval of time is measured by the time it takes internal pressure to increase to a predetermined level in volume chamber 71.

Volume chamber 71 is connected to the top of the diaphragm operator 69 by conduit 72. When the internal pressure of chamber 71 is sutficiently great, the spring beneath the diaphram of the connecting valve 62, is actuated to the position alternate than that illustrated in FIG. 3. Spark pump 67 is then isolated from the source of fluid pressure and the supply fuel for the burner routed into the second path of conduit 70.

The pressure within chamber 71 is developed by effectively connecting the chamber to the source of fluid fuel in conduit 61. Conduit 74 forms a connection between conduits 61 and chamber 71 through orifice 73. Until burner 63 reaches a predetermined level of combustion temperature, volume chamber 71 is continually bled to prevent its internal pressure from increasing. Once this bleed is stopped, the pressure within chamber '71 increases at a rate determined by the size of orifice 73. At a predetermined value of the internal pressure, connecting valve 62 is actuated and spark pump 67 shut down.

Volume chamber 71 remains pressured as long as pilot burner 63 maintains a predetermined level of combustion temperature. When burner 63 is extinguished, volume chamber 71 is bled down to a value at which connecting valve 62. is returned to the position illustrated in FIG. 3.

Main burner supply Conduit 66 has been heretofore described as a source of fluid fuel for the system of FIG. 3. To this point, a portion of the fluid fuel removed into conduit 61 has been disclosed for carrying out two functions. First, a pilot burner 63 has been supplied the fuel for combustion. Second, the pressure of the fuel has been transduced into an igniting spark. Consideration is now given to the function of making the fuel in conduit 60 available to main burner 75.

Main burner 75 is basically similar to pilot burner 63 in that fuel and air are mixed within the burner to propagate a flame as a combutible mixture issues from the burner structure. The pilot burner 63 is positioned so that its combustion will ignite the mixture of fuel and air issuing from the main burner 75. Control valve 76 is provided to connect the conduit 60 to burner 75 when the system functions to prove pilot burner 63 is functioning and available to light the combustible mixture from burner 75.

Control valve 76 specifically connects conduit 60 to conduit 77. Normally, a spring keeps valve 76 shut. This spring force is overcome by the fluid pressure applied in opposition to the spring force. This fluid pressure is developed from the source of fluid fuel in the FIG. 3 disclosure.

A manifold conduit 78 is illustrated as connected to the underside of the valve 76 diaphragm. Branch conduit 78A is connected to the volume chamber 71 through orifice 79. Therefore, the pressure of the fuel of chamber 71 is also available to supply the power to actuate valve 76 when bleed from the manifold is terminated.

Branch manifold 78B connects to heat responsive bleed valve 86 which is quite similar to the heat responsive valve of FIG. 1. Heat responsive bleed valve 80 is operated in the same fashion as the valve of FIG. 1. When the tubular shield of burner 63 elongates under heat, the valve 80 is closed and the pressure in the manifold of conduit 78, 78A, 78B builds up to the operating level of valve 76 by this effective connection of the manifold with the fuel source. At the same time, the internal pressure of chamber 71 reaches the level at which connecting valve 62 is actuated to stop the spark pump 67.

Once control valve 76 is opened, the fuel flows into conduit 77, through the control valve 81 and to burner 75. Control valve 81 is a temperature responsive valve; placed into control of the flow of fuel to main burner 75 from control valve 76. The temperature condition supplied the heat of combustion of the main burner is sensed by element 82. The bulb 82 develops a force which is used to generate a fluid pressure in pipe 83. The control pressure in pipe 83 then positions the control valve 81 to regulate the supply of fuel to burner 75 as required to maintain a predetermined temperature at bulb 82.

General operation The system of FIG. 3 can be readily understood if the functions desired in the system are kept in mind. The system basically functions to suply fuel and an igniting spark to the pilot burner 63 at the same time. When combustion results in shutting the heat responsive bleed valve 80, main fuel valve 76 will be opened and volume chamber '71 pressure will increase at a rate set by orifice 73 until the value of its internal pressure will actuate connecting valve 62 to shut down the spark pump.

Once the main fuel control valve is opened, the fluid supplied main burner 75 will be regulated by heat responsive valve 81. The combustion at main burner 75 will be initiated by pilot burner 63 and burner 63 will stay lit even though regulating valve 81 shuts down main burner 7 5.

Should pilot burner 63 be blown out by a stray wind through opening 84, valve 80 will open when the tubular shield shortens as it cools. When the bleed is re-established through valve 80, main valve 76 closes. Volume chamber 71 then begins to lose pressure through orifice 79 and the now-open bleed valve 80. At the predetermined level of internal pressure within chamber 71, connecting valve 62, is returned to the position illustrated in FIG. 3. The spark pump 67 begins its delivery of an igniting spark to burner 63. This particular system requires that orifice 79 be at least as large as orifice 73 in order for volume chamber 71 to be effectively disconnected from the pressure source of conduit 61 and loose its pressure through valve 80.

The system of FIG. 3 can be classified as automatic. If the various units of the system are normally operative, the supply of fuel to conduit 60 will cause pilot burner 63 to be lit, the burner proved, the spark pump shut down and the main burner 75 lit. When main burner 75 is regulated to an off position, and a stray wind blows out pilot burner 63, the system will automatically attempt to re-ignite pilot burner 63 as long as fuel is made available to conduit 66.

. 1? PEG. 4 MAIN-PILOT BURNER SYSTEM Useful as the system of FIG. 3 is, it nevertheless will continuously cycle in attempting to re-ignite the pilot burner for so longas fluid fuel is supplied conduit 60. To prevent continual, useless operation of the spark pump after a prescribed number of attempts to light a pilot burner, the system disclosed with FIGS. 4, 4A and 413 has been developed.

This system is sufficiently complex in operation to justify the use at least three different drawings to illustrate the system as its units are positioned to cycle the system operation. FIG. 4 illustrates the system as fuel is first made available. Arrows have been used along the con duits to indicate the active flow paths for the fluid fuel at this stage of system operation. The time delay, introduced by the volume chamber, as illustrated as functioning to establish the time for the fuel made available to the pilot burner and spark pump.

FIG. 4A illustrates the fuel source connected to the pilot burner and spark pump. The volume chamber is bleeding off its pressure to set the time when the fuel is supplied the pilot burner and spark pump. Combustion is normally established during this period at the pilot burner.

FIG. 4B shows the volume chamber still bleeding down its pressure, but the spark pump shut down, the pilot burner proved and the main fuel valve open to supply fuel to the main burner. Combustion is normally established at the main burner during this period.

Pilot burner and spark pump supply As is the system of FIG. 3, a source of fluid fuel to the system of these figures is not shown. Conduit 111i is connected to the supply and becomes the source of fuel for conduit 101. Again, arrows are used along the side of the conduits to illustrate the fluid fuel flowing from conduit All, into conduit 1192, through connecting valve 193, through conduit 104, through conduit 105,'through connecting valve 106, through conduit 1117, through conduit 1113 and into volume chamber 1%9.

An orifice is arranged in conduit 1%. This orifice establishes the rate of fuel flow into chamber 109, and, therefore, the time delay between connecting conduit 11341 to the source of fluid fuel and the reaching of a predetermined value of internal pressure within chamber 1&9.

Conduit 104 also takes the fluid fuel to connecting valve 116. The fluid fuel will not pass through valve 11% until the diaphragm operator 111 is actuated by the predetermined pressure in chamber 1119. Once this actuating pressure of chamber 109 is reached, several control actions result as illustrated by the FIG. 4A disclosure.

While Waiting for the internal pressure of chamber 1119 to develop, fluid fuel is simultaneously passing from conduit 101 through conduit 112. Conduit 112 contains an orifice 113, which sets the rate of fluid flow into manifold conduit 114. Within manifold conduit 114, heat responsive bleed valve 115 keeps pressure from developing in conduit 114 until bleed valve 115 is closed by the heat of combustion at the pilot burner. Meanwhile, the arrows indicate the bleed of fluid fuel from this manifold during this time delay.

When the chamber 109 pressure is reached, the force of the pressure is applied to supply fuel to the pilot burner 116 and simultaneously operate spark pump 117. At the same time, chamber 199 begins to exhaust through orifice 118. The spark pump 117 will continue to operate, but only during the period the pressure of chamber 109 decreases to a predetermined value. When the pressure of chamber 109 is lowered sufficiently, the spring of operator 111 repositions connecting valve 110 to the position of FIG. 4 and the spark pump is shut down.

Volume chamber operation in FIG. 4A

FIG. 4A illustrates the function of the volume chamber 1199 in establishing a limited source of fuel for pilot burner 116 and a limited source of pressure for spark pump 117. In actuating connecting valve 110 to apply the fluid pressure fuel of conduit 104 to pilot burner 116 and spark pump 117, the chamber 109 also applies the pressure of the fluid fuel to establishing a bleed for the fluid fuel from chamber 109 and through orifice 11%.

Specifically, FIG. 4A shows diaphragm operator 111 positioned against its spring to actuate connecting valve 110 to connect conduit 104 to conduit 120. Conduit 120 branches into conduit 121 to supply the fuel to pilot burner 116. Also, conduit 120 branches into conduit 122 to supply fuel pressure to spark pump 117. Conduit 121) terminates in diaphragm operator 123 to actuate connecting valve 106 to one of its alternate positions. Once the force of the internal pressure within chamber 169 has provided a path for fuel to burner 116 and power to drive spark pump 117, the time limit is established for providing these actions in actuating diaphragm operator 123 to position connecting valve 106. The actuated connecting valve 106 becomes a bleed path for the flow of fuel from chamber 1119, through orifice 118, thereby setting the time period during which fuel is provided burner 116 along the path of conduit 104, 121) and 121 and the time period during which pressure is provided to drive spark pump 117 with the path of conduits 1114, 120, 122.

Combustion should be established at pilot burner 116 during the time period established by chamber 109. When the heat of pilot burner 116 combustion reaches a predetermined level, heat responsive bleed valve 115 is closed by elongation of the shield of burner 116. The operation of valve 115 is similar to that of valve 7 in PEG. 1 and valve in FIG. 3. Closure of valve 115 marks the proving of pilot burner 116, i.e. the establishment of combustion of burner 116- which can be used to light the main burner. FIG. 48 illustrates the control actions which result from closing valve 115.

Main burner operation in FIG. 4B

FIG. 4B illustrates the position of the system units when the main burner is in operation and the volume chamber 109 has not yet depleted its internal pressure to the level at which connecting valve has been returned to the FIG. 4 position. The bleed valve is closed. Closure of valve 115 brings manifold conduit 114 to the internal pressure of the fuel source. Several control actions take place under the force of fluid pressure in conduit 114.

First, of course, fuel is made available to main burner 13%. Main valve 131 is opened by the pressure of conduit 114 and conduit 100 thereby connected to conduit 132. The amount of fuel actually passed to burner is regulated by valve 133. Valve 133 is brought under the control of the system responsive to the temperature of the conditions supplied the combustion heat of burner 130. Temperature responsive bulb 134 is the primary element developing a fluid pressure control signal in pipe 135. This control signal is applied to modulate the position of valve 133.

Second, the fluid pressure of conduit 114 is applied to diaphragm operator 136 to position both connecting valve 103 and connecting valve 137 to their alternate positions. As seen in FIGS 4 and 4A, valve 193 has been initially positioned to connect conduit 102 to conduit 104. Fuel flows through connecting valve 103 to pilot burner 116. Now with pilot burner 116 proved, connecting valve 103 disconnects conduit 1134 from conduit 1&2 and connects conduit 138 to conduit 1112.

Conduit 138 becomes the second, or alternate, path for fluid fuel from the source to pilot burner 116.

9 Check valves 139 and 140 keep the fuel flowing from either, or both, conduits 121 and 138 to pilot burner 116. With connecting valve 103 in this second position, the fuel for the pilot is routed more directly to the burner for as long as valve 115 remains closed under the control of combustion heat generated by burner 116.

At the same time connecting valve 103 is positioned to change the path of pilot burner fuel, connecting valve 137 is positioned to open conduit 141 to atmosphere bleed. Conduit 141 is connected to conduit 107 and 108 below orifice 118, so the bleed of pressure from chamber 109 continues when connecting valve 106 is simultaneously repositioned by the conduit 114 pressure to block atmosphere bleed through valve 106.

Connecting valve 106 is returned to its original position by the conduit 114- pressure. This conduit 114 pressure becomes effective When chamber 109 is bled down to a pressure which is overcome by the opposing force of pressure in conduit 114.

The return of connecting valve 106 to its original position by conduit 114 pressure is very important to this embodiment of the invention. In the original, FIG. 4, position, connecting valve 106 will again pass fuel to chamber 109 should pilot burner 116 be accidentally blown out, and bleed valve 115 opened to let the spring of position 136 return connecting valve 103 to its FIG. 4 position. The igniting cycle will then begin again and if combustion at pilot burner 116 is proven, fuel will again be available to the main burner 130.

Note that if pilot burner 116 is not proved, the manifold conduit 120 pressure will keep connecting valve 106 in the FIG. 4A, 4B position. Therefore, when chamber 109 pressure is exhausted, the spark pump 117 will be isolated from fuel pressure and fuel will be isolated from pilot burner 116 by the return of connecting valve 110 to its original FIG. 4 position. Obviously, if combustion at burner 116 is not obtained by the time chamber 109 is exhausted down to its predetermined pressure value, there is a maladjustment, or mechanical failure in the system requiring service. Personnel can make the necessary inspection, repairs and replacement. Then, connecting valve 106 can be positioned by manually depressing stem 142. Fuel will then flow in chamber 109 through orifice 118 and the igniting cycle will begin again. A

GENERAL OPERATION OF THE FIG. 4 SYSTEM In a general sense, the system disclosed by FIGS. 4, 4A and 4B functions to supply a volume chamber through an orifice to develop an internal pressure Within a predetermined time to actuate a connecting valve which will supply fuel to a pilot burner and fluid pressure of the fuel to a unit developing an electrical spark at the pilot burner. At the same time, a second connecting valve is also actuated by the output of the first valve to connect the volume chamber to exhaust through the orifice. If combustion results at the burner, a valve is provided to respond to the heat of the burner to effectively connect the main burner to the fuel source, effectively disconnect the first connecting valve from the source, and reroute fuel to the pilot burner to insure the pilot burner continuing to receive fuel for its combustion. Should the pilot burner fail to prove itself by the time volume chamber is depleted of its pressure, the cycle of operation will have to be initiated manually after inspection, repair and replacement has satisfied operating personnel that the system will function normally.

If the main burner is shut down by the temperature control system, it may happen that the pilot burner will be blown out by a stray wind. Should this happen, the heat responsive bleed valve will open. The cycle of ignition will begin, but only after the period of time required to bring the volume chamber up to its predetermined pressure. This time is desirable to allow any explosive mixture, which may have collected in the burner housing, to

10 dissipate. The ignition cycle will then proceed in a normal manner if the pilot burner will prove by shutting the heat responsive bleed valve.

From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the method and apparatus.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

The present invention having been described, what is claimed is:

1. A fuel burning system including, a main burner,

a pilot burner positioned to light the main burner, a

source of fuel under pressure,

means continually responsive to the pressure of the fuel for generating a high spark voltage from a reciprocating mechanical motion,

means forming a spark gap electrically connected to the generator of the high spark voltage to be delivered across the gap and ignite the fuel and air mixture from the pilot burner,

a volume chamber connected to the fuel supply to receive fuel and develop a fuel pressure within the chamber,

first conduit means connecting the fuel source to the pilot burner,

a second conduit means connected to said fuel source to apply the pressure of the fuel to the spark generator,

a valve controlling the connection of the second conduit means to the fuel source and actuated by a predetermined value of the fuel pressure developed in the volume chamber to disconnect the second conduit means from the fuel source, and means responsive to the heat of combustion at the pilot burner to apply the fuel pressure effectively to the volume chamber to develop the predetermined value of the fuel pressure Within the volume chamber which will disconnect the second conduit from the fuel source.

2. A fuel burning system including, a main burner,

a pilot burner positioned to light the main burner, a

source of fuel under pressure,

means continually responsive to the pressure of the fuel for generating a high spark voltage from a reciprocating mechanical motion,

means forming a spark gap electrically connected to the generator of the high spark voltage to be delivered across the gap and ignite the fuel and air mixture from the pilot burner,

a volume chamber connected to the fuel supply to receive fuel and develop a fuel pressure within the chamber,

first conduit means for connecting the fuel source to the pilot burner and spark generator,

second conduit means connecting the fuel source to the pilot burner,

a first control valve passing the fuel from the source to the main burner,

third conduit means connecting the control of the first control valve to the fuel source so the pressure of the fuel source may operate the first valve,

a first connecting valve arranged to alternately connect the first conduit means to the fuel source and the second conduit means to the fuel source, the first connecting valve being positioned by the fuel pressure developed within the volume chamber,

and means responsive to the heat of combustion 1 l at the pilot burner to effectively connect the third conduit means to the source of fuel, whereby the first control valve passes the fuel from the source to the main burner.

3. A fuelburning system including,

a main burner arranged to receive fluid fuel and mix the fuel with air to propagate a flame, I

a pilot burner mounted to propagate a flame which will light the main burner mixture,

a source of fuel under pressure for both burners,

first conduit means connecting the fuel source to the pilot burner,

ignition means for continually generating a high spark voltage from a reciprocating mechanical motion transduce'd from the fuel pressure and cooperating with the pilot burner to ignite the fuel and air mixture from the pilot burner,

a means connecting the spark generator to the pressure of the fuel source,

a valve controlling the connection of the conduit means to the fuel source and the connection of the spark generator to the pressure of the fuel source,

a volume chamber connected to the fuel source and developing a predetermined internal pressure to actuate the valve to disconnect the conduit means from the fuel source and the spark generator from the fuel source and reconnect the pilot burner directly to the source of fuel, and means responsive to the heat of combustion at the pilot burner to apply fuel pressure effectively to the volume chamber to develop the predetermined value of the fuel pressure within the volume chamber which will actuate the valve.

4. A fuel burning system including,

a main burner arranged to receive fluid fuel and mix the fuel with air to propogate a flame,

a pilot burner mounted to propagate a flame which will light the main burner mixture,

at source of fuel under pressure for both burners,

conduit means connecting the fuel source to the pilot burner,

ignition means for continually generating a high spark voltage from a reciprocating mechanical motion transduced from the fuel pressure and cooperating with the pilot burner to ignite the fuel and air mixture from the pilot burner,

a means connecting the spark generator to the pressure of the fuel source,

a valve controlling the connection of the conduit means to the fuel source and the connection of the spark generator to the pressure of the fuel source,

a volume chamber connected to the fuel source and developing a predetermined internal pressure to actuate the valve to disconnect the conduit means from the fuel source and the spark generator from the fuel source and reconnect the pilot burner directly to the source of fuel,

a main fuel valve controlling the fluid fuel flowing from the source to the main burner,

a conduit manifold supplied the pressure of fluid fuel from the source and connected to open the main fuel valve when fuel pressure in the conduit manifold is raised to a predetermined value.

and a bleed valve connected to the conduit manifold to bleed fuel from the conduit manifold and arranged to be actuated by elongation of the pilot burner body to terminate the bleed of fuel' pressure from the conduit manifold and cause the fuel pressure in the system to develop to the value which opens the main fuel valve.

5. A fuel burning system including",

a main burner adapted to burn a mixture of fluid fuel and air,

a source of fluid fuel under pressure connected to the main burner,

a temperature controlled valve in the connection between the main burner and supply regulated by the temperature maintained by the main burner,

a main fuel valve in the connection between the main burner and source with which the fluid fuel may be isolated from the temperature control valve,

a pilot burner mounted relative to the main burner so the flame propagated will light the main burner mixture of fuel and air,

a spark generator responsive to fluid pressure in producing a reciprocating mechanical motion with which to continuously generate a high spark voltage by mechanically stressing piezoelectric material which is electrically connected to the pilot burner,

a connection for simultaneously supplying fuel from the source to the pilot burner and applying pressure of the fuel to the spark generator, a connecting valve joining the connection to the fuel supply and isolatingthe connection from the fuel supply,

a volume chamber connected to the source of fuel to develop a predetermined internal pressure which is applied to the connecting valve to isolate the connection from the pressure of the fuel supply,

and a temperature responsive means connected to the pilot burner to open the main fuel valve when the temperature of the pilot burner reaches a predetermined value.

6, A fuel burning system including,

a main burner adapted to burn a mixture of fluid fuel and air,

a source of fluid fuel under pressure,

a temperature controlled valve located between the main burner and the source for regulating the flow of fuel from the source to the main burner in accordance with the temperature maintained by the main burner combustion,

a main fuel valve located between the temperature controlled valve and the source for isolating the main burner and temperature controlled valve from the source,

a pilot burner mounted relative to the main burner so the pilot burner flame will light the mixture of fuel and air from the main burner,

a means including a conduit manifold connected to the source of fluid fuel through an orifice to apply pressure to open the main fuel valve and further connected to bleed through a valve which responds to the temperature of the pilot burner to close at a predetermined value of temperature, whereby the pressure in the conduit manifold develops to close the main fuel valve,

2. volume chamber connected to the source of fuel through an orifice to develop a predetermined in- V ternal pressure,

a spark generator responsive to fluid pressure in producing a reciprocating mechanical motion with which to continuously generate a high spark voltage by mechanically stressing piezoelectric material which is electrically connected to the pilot burner,

a connecting valve arranged to normally supply fluid fuel pressure to the pilot burner and spark generator and actuated at the predetermined internal pressure of the volume chamber to disconnect the spark generator from the fluid fuel source.

7. A fuel burning system including,

a main burner in which fuel and air are mixed to burn as the mixture is discharged,

a pilot burner mounted with respect to the main burner so the propagated flame will ignite the mixture discharged from the main burner,

a source of fluid fuel,

an ignition unit electrically connected to the pilot burner and arranged to respond to fluid pressure in producing a reciprocating mechanical motion with and a valve responsive to the heat of pilot burner combustion to make an effective connection of the main burner to the source of fluid fuel and an effective connection of the first connecting valve from the source and an effective disconnection of the volume chamber from the source and return the second connecting valve to its initial position and supply the pilot burner fuel from the source.

8. A fuel burning system including,

a main burner in which fluid fuel and air are mixed to burn as the mixture is discharged,

a pilot burner mounted near the main burner to burn fuel and air in a flame which will ignite the mixture discharged from the main burner,

a source of fuel for the pilot burner,

first conduit means path connected from the source to the pilot burner,

a volume chamber connected to the source so as to receive fuel from the source and develop a predetermined internal pressure within a predetermined period,

a first connecting valve controlling the fluid fuel from the source in the first conduit means to the pilot burner and actuated by the pressure of the volume chamber at the predetermined value developed in the volume chamber, an ignition unit connected to the first conduit means to transduce a'reciprocating mechanical motion from the pressure of the fuel in the path for continuously developing a high spark voltage at the pilot burner when fuel is supplied the pilot burner through the first conduit means,

second conduit means connected from the source to the 'pilot burner,

a heat responsive valve controlling the fluid fuel in i and a third valve controlling the fluid fuel in the third conduit supplied the main burner and actuated by the second valve to connect the main burner to the source when the combustion heat at the pilot burner reaches a predetermined level.

9. A fuel burning system including,

a main burner in which fluid fuel and air are mixed to burn as the mixture is discharged,

a pilot burner mounted near the main burner to burn fuel and air in a flame which will ignite the mixture discharged from the main burner,

a source of fuel for the pilot burner,

first conduit means connecting the source with the pilot burner,

a first check valve in the first conduit means to the main flow oriented to allow flow in the path toward the pilot burner,

a pressure actuated three-way valve positioned in the first conduit means and being first actuated to block the flow of fuel from the source through the first check valve and toward the pilot burner while venting the portion of the first conduit means ahead of the first check valve to the atmosphere and being second actuated to permit the unobstructed flow of fuel to the pilot burner from the supply,

a volume chamber connected to the fuel source through an orifice to establish a flow into the chamber which developes a pressure within the chamber to a predetermined value within a predetermined time to actuate the three-way valve to the second of its alternate positions at the predetermined value,

ignition means actuated by the fuel pressure supplied the pilot burner through the three-way valve to produce a reciprocating mechanical motion to continuously develop a high spark voltage at the pilot burner for ignition of fuel and air from the burner,

second conduit means connected from the supply to the pilot burner,

a second check valve in the second conduit means oriented to maintain flow in the path toward the pilot burner,

a heat responsive valve connected to the pilot burner and responsive to the heat generated by the pilot burner to control the fluid fuel from the source so as to divert the fluid fuel from the volume chamber and the three-way valve and into the second conduit means when the combustion heat reaches a predetermined level,

a source of fluid fuel for the main burner,

third conduit means connected from the source of fluid fuel to the main burner,

and a main fuel valve in the third conduit means connected to the main burner and actuated by the heat responsive valve to connect the main burner to the source when the combustion heat at the pilot burner reaches a predetermined level.

10. A fuel burning system including,

a source of fluid fuel,

a pilot burner,

conduit means connected to the source of fuel and the burner,

, a fluid pressure driven ignition means electrically connected to the pilot burner to produce a reciprocating mechanical motion in continuously producing a high spark voltage at the pilot burner to ignite a mixture of air and fuel issuing from the burner,

a volume chamber adapted for connection to the fuel source through an orifice to establish the rate at which the internal pressure of the chamber reaches a predetermined value,

a first connecting valve alternately connecting the volume chamber to the source of fuel and atmosphere exhaust while actuated to the alternate position by fluid pressures,

a second connecting valve responsive to the volume chamber pressure for alternately connecting the high spark voltage generated and the first connecting valveto the fuel source when the pressure in the chamber reaches a predetermined value,

whereby the second connecting valve is carried to its alternate position in which the chamber is exhausted through the orifice and from which alternate position the second connecting valve is returned to its original position in which it selectively connects the chamber to the fuel source by a fluid pressure force representative of combustion at the pilot burner,

a main fuel valve controlling the connection of the fuel source to the main burner,

and a valve arranged to be actuated by the heat of combustion at the pilot burner to direct a fluid pressure when a predetermined combustion level is reached at the pilot burner in opening the main fuel valve and operating the first connecting valve to re- 1 5 turn the first connecting valve to it's original position.

11. A fuel burning system including,

a burner structure,

a source of fluid fuel connected to the burner,

a transducer, means connected between the burner and source of fuel and continually reciprocating a mechanical member of the transducer when receiving the pressu'ral energy of the fuel,

a linkage system connected to the mechanical member of the transducer,

a material with piezoelectric electric properties connected to the linkage system so as to be stressed and develop electrical energy,

ignition means cooperating with the burner structure and connected to receive the electrical energy output of the piezoelectric material to develop a high spark voltage in the fuel and air mixture from the burner to ignite the mixture,

and means responsive to the heat of combustion for disconnecting the pressural energy of the fluid fuel from the transducer when the heat of combustion reaches a predetermined degree.

12. A fuel burning system including,

a burner structure,

a source of fluid fuel connected to the burner,

a transducer, means connected between the burner and source of fuel and reciprocating a mechanical member of the transducer with the pressural energy of the fuel,

a linkage system connected to the mechanical member of the transducer,

material capable of developing piezoelectricity when mechanically stressed connected to the linkage system so as to be stressed to produce electrical energy,

ignition means cooperating with the burner structure and connected to receive the electrical energy output of the piezoelectric material to develop a high spark voltage in the fuel and air mixture from the burner to ignite the mixture,

a valve connected between the source of fuel and transducer to isolate the transducer from the fuel,

and means responsive to the heat of the mixture ignited at the burner to actuate the valve and isolate the transducer from the fuel when a predetermined degree of heat is obtained.

13. A fuel burning system including,

a source of fluid fuel,

a burner connected to the source of fuel,

means forming an electrical spark gap mounted on the burner so a high spark voltage across the gap will ignite a fuel and air mixture from the burner,

a pressure-stressed body connected to the spark gap so as to deliver electrical energy to the gap and form a high spark voltage across the gap when the body is stressed,

a transducer, means connected between the burner and source of fuel and continually reciprocating a mechanical member of the transducer with the pressural en g 9 t e ue a linkage system between the mechanical member of the transducer and the pressure-stressed body to stress t b y,

a body heated by the burner combustion,

and means responsive to the elongation of the body heated by the burner combustion and arranged to disconnect the fuel from the transducer when the heated body is elongated a predetermined amount.

14. A fuel burning system including,

a burner structure,

a source of fluid fuel connected to the burner,

a snap-acting three-way valve connected to the source of fluid fuel and exhaust,

a diaphragm operator mechanically connected to the three-way valve to actuate the valve and cause the valveto alternately connect the diaphragm operator to the pressure of the source and exhaust,

a stern connected to the diaphragm operator for continual reciprocation as the operator is alternately connected to pressure and exhaust through the threeway valve, 7

a valve arranged to normally connect the three-way valve to the pressure source, a

means responsive to the heat of the combustion at the burner for, closing the normally open valve at a predetermined degree of burner heat,

a ceramic material electrically connected to deliver an igniting high spark voltage to the burner when the ceramic material is mechanically stressed,

and a lever for applying the reciprocating movement of the diaphragm stem to the ceramic material and thereby mechanical stress the ceramic material.

15. A fuel burning system including,

a burner structure,

a member heated by the flame of the burner structure to elongate in a physical dimension,

a valve connected to the heated member so the expansion of the member will cause the valve to be actuated when the flame of the burner has brought the heated member to a predetermined temperature,

a source of fluid fuel under pressure,

a transducer, means continually reciprocating a mechanical member of the transducer with the pressural energy of the fuel to produce a high spark voltage at the burner structure,

and conduit means connecting the source to the burner and transducer in parallel to produce a flame at the burner and controlled by the valve actuation to disconnect the transducer from the source at a predetermined temperature of the heated member.

References Cited in the file of this patent UNITED STATES PATENTS 2,125,473 Vaughan Aug. 2, 1938 2,305,242 English Dec. 15, 1942 2,346,704 Ray Apr. 18, 1944 2,456,147 Ray Dec. 14, 1948 2,717,916 Harkness Sept. 13, 1955 2,870,835 Ludgren Jan. 27, 1959 

15. A FUEL BURNING SYSTEM INCLUDING, A BURNER STRUCTURE, A MEMBER HEATED BY THE FLAME OF THE BURNER STRUCTURE TO ELONGATE IN A PHYSICAL DIMENSION, A VALVE CONNECTED TO THE HEATED MEMBER SO THE EXPANSION OF THE MEMBER WILL CAUSE THE VALVE TO BE ACTUATED WHEN THE FLAME OF THE BURNER HAS BROUGHT THE HEATED MEMBER TO A PREDETERMINED TEMPERATURE, A SOURCE OF FLUID FUEL UNDER PRESSURE, A TRANSDUCER, MEANS CONTINUALLY RECIPROCATING A MECHANICAL MEMBER OF THE TRANSDUCER WITH THE PRESSURAL ENERGY OF THE FUEL TO PRODUCE A HIGH SPARK VOLTAGE AT THE BURNER STRUCTURE, AND CONDUIT MEANS CONNECTING THE SOURCE TO THE BURNER AND TRANSDUCER IN PARALLEL TO PRODUCE A FLAME AT THE BURNER AND CONTROLLED BY THE VALVE ACTUATION TO DISCONNECT THE TRANSDUCER FROM THE SOURCE AT A PREDETERMINED TEMPERATURE OF THE HEATED MEMBER. 